Field of the Invention
EP-0 646 704 A1 disclosed a method for regulating a gas turbo-generator set. This gas turbo-generator set consists essentially of a compressor unit, an HP combustion chamber, an HP turbine, an LP combustion chamber, an LP turbine and a generator. The fuel quantity for the HP combustion chamber is dimensioned by means of a corrected temperature signal which is formed by the value of the temperature at the outlet of the LP turbine, minus the respective temperature rise detectable there. This temperature signal is recorded by subtracting the generated temperature rise caused by the fuel quantity introduced into the LP combustion chamber from the measured temperature at the outlet of the LP turbine. The uncorrected temperature signal at the outlet of the LP turbine is used for dimensioning the fuel quantity for the LP combustion chamber.
In this method, the temperatures which are indispensable for regulation are recorded at locations where there is reliable technical implementation and repeatability. In this case, this regulating concept assumes that a temperature increase at the outlet of the LP turbine caused by the firing of the LP combustion chamber, can be recorded repeatably. A regulating concept for the metering of fuel into the two combustion chambers can be drawn up accordingly by means of this procedure.
Although this regulating concept makes it possible to control fuel metering effectively, it is repeatedly evident that sudden unforeseen disturbances, which have an indirect or direct effect on the process temperatures, cannot be mastered by regulation, as the situation arises, due to the inherent inertias of such a system.